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-rw-r--r--packages/gcc/13.3.0/0012-libgcc-m68k-Fixes-for-soft-float.patch349
1 files changed, 349 insertions, 0 deletions
diff --git a/packages/gcc/13.3.0/0012-libgcc-m68k-Fixes-for-soft-float.patch b/packages/gcc/13.3.0/0012-libgcc-m68k-Fixes-for-soft-float.patch
new file mode 100644
index 00000000..caa6664a
--- /dev/null
+++ b/packages/gcc/13.3.0/0012-libgcc-m68k-Fixes-for-soft-float.patch
@@ -0,0 +1,349 @@
+From 51345476fc2f83c77736fab8e29ff4ac358d0f2e Mon Sep 17 00:00:00 2001
+From: Keith Packard <keithp@keithp.com>
+Date: Tue, 22 Aug 2023 12:28:53 -0700
+Subject: [PATCH] libgcc/m68k: Fixes for soft float
+
+Check for non-zero denorm in __adddf3. Need to check both the upper and
+lower 32-bit chunks of a 64-bit float for a non-zero value when
+checking to see if the value is -0.
+
+Fix __addsf3 when the sum exponent is exactly 0xff to ensure that
+produces infinity and not nan.
+
+Handle converting NaN/inf values between formats.
+
+Handle underflow and overflow when truncating.
+
+Write a replacement for __fixxfsi so that it does not raise extra
+exceptions during an extra conversion from long double to double.
+
+Return correctly signed zero on float and double divide underflow
+
+Return positive qNaN instead of negative.
+
+Signed-off-by: Keith Packard <keithp@keithp.com>
+---
+ libgcc/config/m68k/fpgnulib.c | 170 +++++++++++++++++++++++++++-------
+ libgcc/config/m68k/lb1sf68.S | 20 ++--
+ 2 files changed, 147 insertions(+), 43 deletions(-)
+
+diff --git a/libgcc/config/m68k/fpgnulib.c b/libgcc/config/m68k/fpgnulib.c
+index fe41edf26aa0..eaa7858493c9 100644
+--- a/libgcc/config/m68k/fpgnulib.c
++++ b/libgcc/config/m68k/fpgnulib.c
+@@ -54,6 +54,7 @@
+ #define SIGNBIT 0x80000000L
+ #define HIDDEN (1L << 23L)
+ #define SIGN(fp) ((fp) & SIGNBIT)
++#define EXPMASK 0xFFL
+ #define EXP(fp) (((fp) >> 23L) & 0xFF)
+ #define MANT(fp) (((fp) & 0x7FFFFFL) | HIDDEN)
+ #define PACK(s,e,m) ((s) | ((e) << 23L) | (m))
+@@ -262,6 +263,9 @@ __extendsfdf2 (float a1)
+ mant &= ~HIDDEN;
+ }
+ exp = exp - EXCESS + EXCESSD;
++ /* Handle inf and NaN */
++ if (exp == EXPMASK - EXCESS + EXCESSD)
++ exp = EXPDMASK;
+ dl.l.upper |= exp << 20;
+ dl.l.upper |= mant >> 3;
+ dl.l.lower = mant << 29;
+@@ -295,40 +299,52 @@ __truncdfsf2 (double a1)
+ /* shift double mantissa 6 bits so we can round */
+ sticky |= mant & ((1 << 6) - 1);
+ mant >>= 6;
+-
+- /* Check for underflow and denormals. */
+- if (exp <= 0)
++ if (exp == EXPDMASK - EXCESSD + EXCESS)
+ {
+- if (exp < -24)
++ exp = EXPMASK;
++ mant = mant >> 1 | (mant & 1) | !!sticky;
++ }
++ else
++ {
++ /* Check for underflow and denormals. */
++ if (exp <= 0)
+ {
+- sticky |= mant;
++ if (exp < -24)
++ {
++ sticky |= mant;
++ mant = 0;
++ }
++ else
++ {
++ sticky |= mant & ((1 << (1 - exp)) - 1);
++ mant >>= 1 - exp;
++ }
++ exp = 0;
++ }
++
++ /* now round */
++ shift = 1;
++ if ((mant & 1) && (sticky || (mant & 2)))
++ {
++ int rounding = exp ? 2 : 1;
++
++ mant += 1;
++
++ /* did the round overflow? */
++ if (mant >= (HIDDEN << rounding))
++ {
++ exp++;
++ shift = rounding;
++ }
++ }
++ /* shift down */
++ mant >>= shift;
++ if (exp >= EXPMASK)
++ {
++ exp = EXPMASK;
+ mant = 0;
+ }
+- else
+- {
+- sticky |= mant & ((1 << (1 - exp)) - 1);
+- mant >>= 1 - exp;
+- }
+- exp = 0;
+ }
+-
+- /* now round */
+- shift = 1;
+- if ((mant & 1) && (sticky || (mant & 2)))
+- {
+- int rounding = exp ? 2 : 1;
+-
+- mant += 1;
+-
+- /* did the round overflow? */
+- if (mant >= (HIDDEN << rounding))
+- {
+- exp++;
+- shift = rounding;
+- }
+- }
+- /* shift down */
+- mant >>= shift;
+
+ mant &= ~HIDDEN;
+
+@@ -432,8 +448,31 @@ __extenddfxf2 (double d)
+ }
+
+ exp = EXPD (dl) - EXCESSD + EXCESSX;
+- ldl.l.upper |= exp << 16;
++ dl.l.upper &= MANTDMASK;
+ ldl.l.middle = HIDDENX;
++
++ /* Recover from a denorm. */
++ if (exp == -EXCESSD + EXCESSX)
++ {
++ exp++;
++ while ((dl.l.upper & HIDDEND) == 0)
++ {
++ exp--;
++ dl.l.upper = (dl.l.upper << 1) | (dl.l.lower >> 31);
++ dl.l.lower = dl.l.lower << 1;
++ }
++ }
++
++ /* Handle inf and NaN */
++ else if (exp == EXPDMASK - EXCESSD + EXCESSX)
++ {
++ exp = EXPXMASK;
++ /* No hidden one bit for INF */
++ if (dl.l.upper == 0 && dl.l.lower == 0)
++ ldl.l.middle = 0;
++ }
++
++ ldl.l.upper |= exp << 16;
+ /* 31-20: # mantissa bits in ldl.l.middle - # mantissa bits in dl.l.upper */
+ ldl.l.middle |= (dl.l.upper & MANTDMASK) << (31 - 20);
+ /* 1+20: explicit-integer-bit + # mantissa bits in dl.l.upper */
+@@ -464,9 +503,38 @@ __truncxfdf2 (long double ld)
+ }
+
+ exp = EXPX (ldl) - EXCESSX + EXCESSD;
+- /* ??? quick and dirty: keep `exp' sane */
+- if (exp >= EXPDMASK)
+- exp = EXPDMASK - 1;
++ /* Check for underflow and denormals. */
++ if (exp <= 0)
++ {
++ if (exp < -53)
++ {
++ ldl.l.middle = 0;
++ ldl.l.lower = 0;
++ }
++ else if (exp < -30)
++ {
++ ldl.l.lower = (ldl.l.middle & MANTXMASK) >> ((1 - exp) - 32);
++ ldl.l.middle &= ~MANTXMASK;
++ }
++ else
++ {
++ ldl.l.lower >>= 1 - exp;
++ ldl.l.lower |= (ldl.l.middle & MANTXMASK) << (32 - (1 - exp));
++ ldl.l.middle = (ldl.l.middle & ~MANTXMASK) | (ldl.l.middle & MANTXMASK >> (1 - exp));
++ }
++ exp = 0;
++ }
++ else if (exp == EXPXMASK - EXCESSX + EXCESSD)
++ {
++ exp = EXPDMASK;
++ ldl.l.middle |= ldl.l.lower;
++ }
++ else if (exp >= EXPDMASK)
++ {
++ exp = EXPDMASK;
++ ldl.l.middle = 0;
++ ldl.l.lower = 0;
++ }
+ dl.l.upper |= exp << (32 - (EXPDBITS + 1));
+ /* +1-1: add one for sign bit, but take one off for explicit-integer-bit */
+ dl.l.upper |= (ldl.l.middle & MANTXMASK) >> (EXPDBITS + 1 - 1);
+@@ -511,10 +579,40 @@ __floatunsixf (unsigned long l)
+
+ /* convert a long double to an int */
+ long
+-__fixxfsi (long double ld)
++__fixxfsi (long double a)
+ {
+- long foo = __fixdfsi ((double) ld);
+- return foo;
++ union long_double_long ldl;
++ long exp;
++ long l;
++
++ ldl.ld = a;
++
++ exp = EXPX(ldl);
++ if (exp == 0 && ldl.l.middle == 0 && ldl.l.lower == 0)
++ return 0;
++
++ exp = exp - EXCESSX - 64;
++
++ if (exp > 0)
++ {
++ /* Return largest integer. */
++ return SIGNX (ldl) ? 0x80000000L : 0x7fffffffL;
++ }
++
++ if (exp <= -64)
++ return 0;
++
++ if (exp <= -32)
++ {
++ ldl.l.lower = ldl.l.middle >> (-exp - 32);
++ }
++ else if (exp < 0)
++ {
++ ldl.l.lower = ldl.l.lower >> -exp;
++ ldl.l.lower |= ldl.l.middle << (32 + exp);
++ }
++
++ return SIGNX(ldl) ? -ldl.l.lower : ldl.l.lower;
+ }
+
+ /* The remaining provide crude math support by working in double precision. */
+diff --git a/libgcc/config/m68k/lb1sf68.S b/libgcc/config/m68k/lb1sf68.S
+index 8ba85c53656d..e12888bd7f89 100644
+--- a/libgcc/config/m68k/lb1sf68.S
++++ b/libgcc/config/m68k/lb1sf68.S
+@@ -635,7 +635,7 @@ SYM (__modsi3):
+ .globl SYM (_fpCCR)
+ .globl $_exception_handler
+
+-QUIET_NaN = 0xffffffff
++QUIET_NaN = 0x7fffffff
+
+ D_MAX_EXP = 0x07ff
+ D_BIAS = 1022
+@@ -700,9 +700,10 @@ Ld$overflow:
+ PICJUMP $_exception_handler
+
+ Ld$underflow:
+-| Return 0 and set the exception flags
++| Return a properly signed 0 and set the exception flags
+ movel IMM (0),d0
+ movel d0,d1
++ orl d7,d0
+ movew IMM (INEXACT_RESULT+UNDERFLOW),d7
+ moveq IMM (DOUBLE_FLOAT),d6
+ PICJUMP $_exception_handler
+@@ -711,6 +712,7 @@ Ld$inop:
+ | Return a quiet NaN and set the exception flags
+ movel IMM (QUIET_NaN),d0
+ movel d0,d1
++ bset IMM (31),d1
+ movew IMM (INEXACT_RESULT+INVALID_OPERATION),d7
+ moveq IMM (DOUBLE_FLOAT),d6
+ PICJUMP $_exception_handler
+@@ -1383,6 +1385,8 @@ Ladddf$a:
+ bge 2f |
+ movel d0,d0 | check for zero, since we don't '
+ bne Ladddf$ret | want to return -0 by mistake
++ movel d1,d1 |
++ bne Ladddf$ret |
+ bclr IMM (31),d7 |
+ bra Ladddf$ret |
+ 2:
+@@ -2080,6 +2084,7 @@ Ldivdf$b$nf:
+ | If d2 == 0x7ff00000 we have to check d3.
+ tstl d3 |
+ bne Ld$inop | if d3 <> 0, b is NaN
++ movel a0,d7 | put a's sign
+ bra Ld$underflow | else b is +/-INFINITY, so signal underflow
+
+ Ldivdf$a$nf:
+@@ -2090,8 +2095,7 @@ Ldivdf$a$nf:
+ | If a is INFINITY we have to check b
+ cmpl d7,d2 | compare b with INFINITY
+ bge Ld$inop | if b is NaN or INFINITY return NaN
+- tstl d3 |
+- bne Ld$inop |
++ movl a0,d7 | restore sign bit to d7
+ bra Ld$overflow | else return overflow
+
+ | If a number is denormalized we put an exponent of 1 but do not put the
+@@ -2186,6 +2190,7 @@ Lround$exit:
+ #endif
+ beq 2f | if not loop back
+ bra 1b |
++ movel a0,d7
+ bra Ld$underflow | safety check, shouldn't execute '
+ 2: orl d6,d2 | this is a trick so we don't lose '
+ orl d7,d3 | the bits which were flushed right
+@@ -2548,7 +2553,7 @@ Lround$to$minus:
+ .globl SYM (_fpCCR)
+ .globl $_exception_handler
+
+-QUIET_NaN = 0xffffffff
++QUIET_NaN = 0x7fffffff
+ SIGNL_NaN = 0x7f800001
+ INFINITY = 0x7f800000
+
+@@ -2614,8 +2619,9 @@ Lf$overflow:
+ PICJUMP $_exception_handler
+
+ Lf$underflow:
+-| Return 0 and set the exception flags
++| Return a properly signed 0 and set the exception flags
+ moveq IMM (0),d0
++ orl d7,d0
+ moveq IMM (INEXACT_RESULT+UNDERFLOW),d7
+ moveq IMM (SINGLE_FLOAT),d6
+ PICJUMP $_exception_handler
+@@ -2936,7 +2942,7 @@ Laddsf$4:
+ #else
+ cmpl IMM (0xff),d2
+ #endif
+- bhi 1f
++ bge 1f
+ bclr IMM (FLT_MANT_DIG-1),d0
+ #ifndef __mcoldfire__
+ lslw IMM (7),d2
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